Many industrial and consumer processes require an energy input, such as a fuel or other fluid (liquid or gas) at a relatively high energy state, and also produce a waste fluid (liquid or gas) at a lower energy state, but which still contains usable energy. There are known machines or processes for capturing some of the remaining energy in the waste fluid, and to use this energy to elevate the energy level of the input fluid in order to yield an overall increase in process efficiency. For example, a combustion engine may be fitted with a turbopump (also known as a turbocharger) that is driven by residual energy in exhaust gases, to increase the fluid pressure in the combustion chambers and yield a higher energy output of the engine than would otherwise be possible. In a similar fashion, energy recovery devices can be employed on reverse osmosis water purification systems, refrigeration processes, steam processes, and chemical refining processes.
Sliding-vane prime mover technology is generally known for use in positive-displacement devices that function by changing chamber volume. The change in chamber volume is accomplished by a sliding vane mounted to a rotor and following a cam-style surface of a rotor casing, which changes the chamber volume as the rotor spins and the sliding vane or vanes are driven along the cam-style surface. Such devices may be driven by an outside power source to produce a pumping or compressing effect, or the pressure or flow energy may be extracted to produce a turbine or expander effect. For example, such devices may be used in hydraulics, cryogenics, industrial fluid transfer, and the like.